Activity of doripenem with and without levofloxacin, amikacin, and colistin against Pseudomonas aeruginosa and Acinetobacter baumannii

At 24 h, sub-MIC doripenem and levofloxacin showed synergy against 21 of 25 Pseudomonas aeruginosa strains, sub-MIC doripenem and amikacin against 22 isolates, and sub-MIC doripenem and colistin against 19 isolates. Of 25 Acinetobacter baumannii strains, sub-MIC doripenem and levofloxacin showed synergy against 11 strains at 24 h, sub-MIC doripenem and amikacin against 24 strains, and sub-MIC doripenem and colistin against all isolates.